Objective: To quantify the susceptibility of carcinoma to hepatic metastases by studying autopsy livers with carcinoma metastases, the primary sites of which were mostly the digestive organs.
Study design: We developed a stereologic method of estimating the total number, N, and the size distribution of metastatic tumors in the liver based on a geometric model of spherical nodules with varying radii, r. This method proved to be sufficiently reliable by disector analysis simultaneously performed in some cases; it gave an approximate result. This method was applied to the 31 autopsy cases. Correlation and regression analyses were performed among N, the mean radius of nodules, rmean, and conventional pathologic features of the primary tumor.
Results: The estimates of N ranged from 10 to 3.2 x 10(5). A close negative correlation was confirmed between N and rmean. Neither significant correlation nor regression was observed among N and the other pathologic factors of the primary tumors.
Conclusion: N turned out to serve as a useful index for evaluating the metastatic potential of a carcinoma. However, investigation has yet to be made to determine biologic factors in the primary tumor closely associated with N.